"These are the voyages of the starship Icarus – this fascinating, seminal 1963 Czech sci-fi was plundered wholesale by Star Trek, including the philosophical homilies by a verbose captain."

London Evening Standard by Steve Morrissey

Well that's unfair. I love Ikarie XB-1 something fierce (as I do Star Trek) but in my eyes both were clearly born of the same inspiration- Forbidden Planet.

Both were indeed influenced by Forbidden Planet (it's hard to ignore Ikarie's Robby-style robot Patrick!), but Roddenberry also borrowed from Ikarie. I'm guessing he didn't see the East German/Polish production The Silent Star (1959), which is actually even closer to Star Trek in that its spaceship's crew is explicitly multiracial as well as international.

"Disorienting and delirious, the latest addition to Second Run's excellent roster of Czech films might be a milestone of sci-fi cinema, but it's also a work of such sophistication that its production values and allegorical intent took this first-time viewer by cumulative surprise."

"Second Run’s restored print looks and sounds marvellous... Ikarie grips as an acutely realised study of what life could actually be like on a fifteen-year space voyage... Production values and design are astonishing, and all is handled with deft, sober intelligence"